Product Description:

The Bosch Rexroth Indramat KDA 3.1-050-3-D0S-U1 belongs to the KDA Spindle Drives series and serves as a closed-loop power module for high-speed machine-tool spindles in automated production lines. By converting intermediate DC link energy into a regulated three-phase output, it keeps spindle speed tightly aligned with digital commands from the CNC controller. That control behavior helps the spindle stay on target during drilling, milling, and similar machining cycles where load can change quickly. The unit is intended for applications that require repeatable speed regulation and fast response from the spindle drive.

Internally, the converter draws its DC link energy from 300 VDC, and the power stage can deliver a continuous 50 A to the spindle motor. A digital speed reference enters through a 16-bit parallel digital interface, giving the controller fine command resolution when spindle speed must follow interpolated CNC motion. For diagnostics and parameter access, the unit includes an RS-232C serial interface. The auxiliary 115 V/50-60 Hz supply powers the dedicated cooling circuit. This series 3 controller omits a second encoder socket, so feedback is limited to the primary resolver and routed through a single feedback path.

The cooling system uses a heat-sink-mounted blower and forced-air cooling, allowing the drive to sustain rated output at ambient temperatures from 5 to 45 °C without derating. Airflow carries heat away from the power semiconductors and supports stable operation during extended spindle duty. Installation is permitted up to 1000 m above sea level, after which output correction is required because lower air density reduces cooling effectiveness. Because no auxiliary encoder input is provided, the primary feedback channel handles orientation and speed loops during operation.